spec: Avoid using makeinstall relic

spec: Avoid using makeinstall relic

The macro was made to help installing broken packages that did not use
DESTDIR correctly by overriding individual path variables (prefix,
sysconfdir, ...). Newer rpm provides fixed make_install macro that calls
make install with just the correct DESTDIR, however it is not available
everywhere (e.g., RHEL 5 does not have it). On the other hand the
make_install macro is simple and straightforward enough for us to use
its expansion directly.